Browsing by Author "Marx, Christine E"

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    A pilot randomized controlled trial with paroxetine for subthreshold PTSD in Operation Enduring Freedom/Operation Iraqi Freedom era veterans
    (Psychiatry Research, 2012-12-31) Naylor, Jennifer C; Dolber, Trygve R; Strauss, Jennifer L; Kilts, Jason D; Strauman, Timothy J; Bradford, Daniel W; Szabo, Steven T; Youssef, Nagy A; Connor, Kathryn M; Davidson, Jonathan RT; Marx, Christine E
    Subthreshold posttraumatic stress disorder (PTSD) is associated with increased risk for suicidality, depression, and functional impairment. We thus conducted a small (N=12) pilot randomized controlled trial (RCT) with paroxetine for subthreshold PTSD in Operation Enduring Freedom/Operation Iraqi Freedom (OEF/OIF) era veterans. Hospital Anxiety and Depression Scale (HADS) scores improved by 30.4% in the paroxetine group. Paroxetine may have promise for subthreshold PTSD.
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    Allopregnanolone Levels Are Inversely Associated with Self-Reported Pain Symptoms in U.S. Iraq and Afghanistan-Era Veterans: Implications for Biomarkers and Therapeutics.
    (Pain Med, 2016-01) Naylor, Jennifer C; Kilts, Jason D; Szabo, Steven T; Dunn, Charlotte E; Keefe, Francis J; Tupler, Larry A; Shampine, Lawrence J; Morey, Rajendra A; Strauss, Jennifer L; Hamer, Robert M; Wagner, H Ryan; MIRECC Workgroup; Marx, Christine E
    BACKGROUND AND OBJECTIVES: Pain symptoms are common among Iraq/Afghanistan-era veterans, many of whom continue to experience persistent pain symptoms despite multiple pharmacological interventions. Preclinical data suggest that neurosteroids such as allopregnanolone demonstrate pronounced analgesic properties, and thus represent logical biomarker candidates and therapeutic targets for pain. Allopregnanolone is also a positive GABAA receptor modulator with anxiolytic, anticonvulsant, and neuroprotective actions in rodent models. We previously reported inverse associations between serum allopregnanolone levels and self-reported pain symptom severity in a pilot study of 82 male veterans. METHODS: The current study investigates allopregnanolone levels in a larger cohort of 485 male Iraq/Afghanistan-era veterans to attempt to replicate these initial findings. Pain symptoms were assessed by items from the Symptom Checklist-90-R (SCL-90-R) querying headache, chest pain, muscle soreness, and low back pain over the past 7 days. Allopregnanolone levels were quantified by gas chromatography/mass spectrometry. RESULTS: Associations between pain ratings and allopregnanolone levels were examined with Poisson regression analyses, controlling for age and smoking. Bivariate nonparametric Mann–Whitney analyses examining allopregnanolone levels across high and low levels of pain were also conducted. Allopregnanolone levels were inversely associated with muscle soreness [P = 0.0028], chest pain [P = 0.032], and aggregate total pain (sum of all four pain items) [P = 0.0001]. In the bivariate analyses, allopregnanolone levels were lower in the group reporting high levels of muscle soreness [P = 0.001]. CONCLUSIONS: These findings are generally consistent with our prior pilot study and suggest that allopregnanolone may function as an endogenous analgesic. Thus, exogenous supplementation with allopregnanolone could have therapeutic potential. The characterization of neurosteroid profiles may also have biomarker utility.
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    An epigenome-wide association study of posttraumatic stress disorder in US veterans implicates several new DNA methylation loci.
    (Clinical epigenetics, 2020-03) Logue, Mark W; Miller, Mark W; Wolf, Erika J; Huber, Bertrand Russ; Morrison, Filomene G; Zhou, Zhenwei; Zheng, Yuanchao; Smith, Alicia K; Daskalakis, Nikolaos P; Ratanatharathorn, Andrew; Uddin, Monica; Nievergelt, Caroline M; Ashley-Koch, Allison E; Baker, Dewleen G; Beckham, Jean C; Garrett, Melanie E; Boks, Marco P; Geuze, Elbert; Grant, Gerald A; Hauser, Michael A; Kessler, Ronald C; Kimbrel, Nathan A; Maihofer, Adam X; Marx, Christine E; Qin, Xue-Jun; Risbrough, Victoria B; Rutten, Bart PF; Stein, Murray B; Ursano, Robert J; Vermetten, Eric; Vinkers, Christiaan H; Ware, Erin B; Stone, Annjanette; Schichman, Steven A; McGlinchey, Regina E; Milberg, William P; Hayes, Jasmeet P; Verfaellie, Mieke; Traumatic Stress Brain Study Group

    Background

    Previous studies using candidate gene and genome-wide approaches have identified epigenetic changes in DNA methylation (DNAm) associated with posttraumatic stress disorder (PTSD).

    Methods

    In this study, we performed an EWAS of PTSD in a cohort of Veterans (n = 378 lifetime PTSD cases and 135 controls) from the Translational Research Center for TBI and Stress Disorders (TRACTS) cohort assessed using the Illumina EPIC Methylation BeadChip which assesses DNAm at more than 850,000 sites throughout the genome. Our model included covariates for ancestry, cell heterogeneity, sex, age, and a smoking score based on DNAm at 39 smoking-associated CpGs. We also examined in EPIC-based DNAm data generated from pre-frontal cortex (PFC) tissue from the National PTSD Brain Bank (n = 72).

    Results

    The analysis of blood samples yielded one genome-wide significant association with PTSD at cg19534438 in the gene G0S2 (p = 1.19 × 10-7, padj = 0.048). This association was replicated in an independent PGC-PTSD-EWAS consortium meta-analysis of military cohorts (p = 0.0024). We also observed association with the smoking-related locus cg05575921 in AHRR despite inclusion of a methylation-based smoking score covariate (p = 9.16 × 10-6), which replicates a previously observed PGC-PTSD-EWAS association (Smith et al. 2019), and yields evidence consistent with a smoking-independent effect. The top 100 EWAS loci were then examined in the PFC data. One of the blood-based PTSD loci, cg04130728 in CHST11, which was in the top 10 loci in blood, but which was not genome-wide significant, was significantly associated with PTSD in brain tissue (in blood p = 1.19 × 10-5, padj = 0.60, in brain, p = 0.00032 with the same direction of effect). Gene set enrichment analysis of the top 500 EWAS loci yielded several significant overlapping GO terms involved in pathogen response, including "Response to lipopolysaccharide" (p = 6.97 × 10-6, padj = 0.042).

    Conclusions

    The cross replication observed in independent cohorts is evidence that DNA methylation in peripheral tissue can yield consistent and replicable PTSD associations, and our results also suggest that that some PTSD associations observed in peripheral tissue may mirror associations in the brain.
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    Effects of chronic mild traumatic brain injury on white matter integrity in Iraq and Afghanistan war veterans.
    (Human Brain Mapping, 2013-11) Morey, Rajendra A; Haswell, Courtney C; Selgrade, Elizabeth S; Massoglia, Dino; Liu, Chunlei; Weiner, Jonathan; Marx, Christine E; MIRECC Work Group; Cernak, Ibolja; McCarthy, Gregory
    Mild traumatic brain injury (TBI) is a common source of morbidity from the wars in Iraq and Afghanistan. With no overt lesions on structural MRI, diagnosis of chronic mild TBI in military veterans relies on obtaining an accurate history and assessment of behavioral symptoms that are also associated with frequent comorbid disorders, particularly posttraumatic stress disorder (PTSD) and depression. Military veterans from Iraq and Afghanistan with mild TBI (n = 30) with comorbid PTSD and depression and non-TBI participants from primary (n = 42) and confirmatory (n = 28) control groups were assessed with high angular resolution diffusion imaging (HARDI). White matter-specific registration followed by whole-brain voxelwise analysis of crossing fibers provided separate partial volume fractions reflecting the integrity of primary fibers and secondary (crossing) fibers. Loss of white matter integrity in primary fibers (P < 0.05; corrected) was associated with chronic mild TBI in a widely distributed pattern of major fiber bundles and smaller peripheral tracts including the corpus callosum (genu, body, and splenium), forceps minor, forceps major, superior and posterior corona radiata, internal capsule, superior longitudinal fasciculus, and others. Distributed loss of white matter integrity correlated with duration of loss of consciousness and most notably with "feeling dazed or confused," but not diagnosis of PTSD or depressive symptoms. This widespread spatial extent of white matter damage has typically been reported in moderate to severe TBI. The diffuse loss of white matter integrity appears consistent with systemic mechanisms of damage shared by blast- and impact-related mild TBI that involves a cascade of inflammatory and neurochemical events.
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    Gene Expression Analysis in Three Posttraumatic Stress Disorder Cohorts Implicates Inflammation and Innate Immunity Pathways and Uncovers Shared Genetic Risk With Major Depressive Disorder.
    (Frontiers in neuroscience, 2021-01) Garrett, Melanie E; Qin, Xue Jun; Mehta, Divya; Dennis, Michelle F; Marx, Christine E; Grant, Gerald A; VA Mid-Atlantic MIRECC Workgroup; PTSD Initiative; Injury and Traumatic Stress (INTRuST) Clinical Consortium; Psychiatric Genomics Consortium PTSD Group; Stein, Murray B; Kimbrel, Nathan A; Beckham, Jean C; Hauser, Michael A; Ashley-Koch, Allison E
    Posttraumatic stress disorder (PTSD) is a complex psychiatric disorder that can develop following exposure to traumatic events. The Psychiatric Genomics Consortium PTSD group (PGC-PTSD) has collected over 20,000 multi-ethnic PTSD cases and controls and has identified both genetic and epigenetic factors associated with PTSD risk. To further investigate biological correlates of PTSD risk, we examined three PGC-PTSD cohorts comprising 977 subjects to identify differentially expressed genes among PTSD cases and controls. Whole blood gene expression was quantified with the HumanHT-12 v4 Expression BeadChip for 726 OEF/OIF veterans from the Veterans Affairs (VA) Mental Illness Research Education and Clinical Center (MIRECC), 155 samples from the Injury and Traumatic Stress (INTRuST) Clinical Consortium, and 96 Australian Vietnam War veterans. Differential gene expression analysis was performed in each cohort separately followed by meta-analysis. In the largest cohort, we performed co-expression analysis to identify modules of genes that are associated with PTSD and MDD. We then conducted expression quantitative trait loci (eQTL) analysis and assessed the presence of eQTL interactions involving PTSD and major depressive disorder (MDD). Finally, we utilized PTSD and MDD GWAS summary statistics to identify regions that colocalize with eQTLs. Although not surpassing correction for multiple testing, the most differentially expressed genes in meta-analysis were interleukin-1 beta (IL1B), a pro-inflammatory cytokine previously associated with PTSD, and integrin-linked kinase (ILK), which is highly expressed in brain and can rescue dysregulated hippocampal neurogenesis and memory deficits. Pathway analysis revealed enrichment of toll-like receptor (TLR) and interleukin-1 receptor genes, which are integral to cellular innate immune response. Co-expression analysis identified four modules of genes associated with PTSD, two of which are also associated with MDD, demonstrating common biological pathways underlying the two conditions. Lastly, we identified four genes (UBA7, HLA-F, HSPA1B, and RERE) with high probability of a shared causal eQTL variant with PTSD and/or MDD GWAS variants, thereby providing a potential mechanism by which the GWAS variant contributes to disease risk. In summary, we provide additional evidence for genes and pathways previously reported and identified plausible novel candidates for PTSD. These data provide further insight into genetic factors and pathways involved in PTSD, as well as potential regions of pleiotropy between PTSD and MDD.
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    Widespread Cortical Thickness Is Associated With Neuroactive Steroid Levels.
    (Frontiers in Neuroscience, 2019-01) Morey, Rajendra A; Davis, Sarah L; Haswell, Courtney C; Naylor, Jennifer C; Kilts, Jason D; Szabo, Steven T; Shampine, Larry J; Parke, Gillian J; Sun, Delin; Swanson, Chelsea A; Wagner, Henry R; Mid-Atlantic MIRECC Workgroup; Marx, Christine E
    Background:Neuroactive steroids are endogenous molecules with regenerative and neuroprotective actions. Both cortical thickness and many neuroactive steroid levels decline with age and are decreased in several neuropsychiatric disorders. However, a systematic examination of the relationship between serum neuroactive steroid levels and in vivo measures of cortical thickness in humans is lacking. Methods:Peripheral serum levels of seven neuroactive steroids were assayed in United States military veterans. All (n = 143) subsequently underwent high-resolution structural MRI, followed by parcellelation of the cortical surface into 148 anatomically defined regions. Regression modeling was applied to test the association between neuroactive steroid levels and hemispheric total gray matter volume as well as region-specific cortical thickness. False discovery rate (FDR) correction was used to control for Type 1 error from multiple testing. Results:Neuroactive steroid levels of allopregnanolone and pregnenolone were positively correlated with gray matter thickness in multiple regions of cingulate, parietal, and occipital association cortices (r = 0.20-0.47; p < 0.05; FDR-corrected). Conclusion:Positive associations between serum neuroactive steroid levels and gray matter cortical thickness are found in multiple brain regions. If these results are confirmed, neuroactive steroid levels and cortical thickness may help in monitoring the clinical response in future intervention studies of neuroregenerative therapies.